1. Field of the Invention
The present invention relates to an endoscope system that transmits a signal by means of a capacitive coupling.
2. Description of Related Art
Conventionally, endoscope systems generally include an endoscope having an insertion part inserted into the interior of a living body, and an extracorporeal device such as a monitor installed outside the living body. To transfer a signal between the endoscope and the extracorporeal device, electrodes installed on both the endoscope and the extracorporeal device are brought into direct contact with each other. Thus, a control signal or an image signal is transferred.
When the insertion part is inserted into the living body, a fluid from the living body is attached to the insertion part. As such, after the endoscope is used, the whole endoscope including a scope-side connector (first scope-side signal connection part) connected to the extracorporeal device needs to be sterilized, for instance, by cleaning equipment. Further, although the extracorporeal device has a low possibility of the fluid from the living body being attached thereto, the extracorporeal device is required to be kept clean in order to prevent infection. Particularly, since an extracorporeal connector (first extracorporeal signal connection part) of the extracorporeal device which is connected to the scope-side connector has a high chance of coming in contact with a person, it is necessary to keep the extracorporeal connector clean at all times by wiping it with an antiseptic solution.
For this reason, as disclosed, for example, in Japanese Unexamined Patent Application, First Publication No. 2007-097767, an electronic endoscope system (endoscope system) that transfers a signal by means of capacitive coupling without bringing electrodes into direct contact with each other has been proposed.
In the electronic endoscope system, a universal cord provided to an intracorporeal device (endoscope) is connected to an extracorporeal device. A pair of mutually detachable connectors (signal connection parts) is installed on connection parts of the universal cord and the extracorporeal device. The connector of the intracorporeal device includes a first circular pad (electrode) disposed at the central part thereof, and a second annular pad disposed so as to surround the first pad. Further, the connector of the extracorporeal device includes a third pad disposed at the central part thereof, and a fourth annular pad disposed so as to surround the third pad.
When the pair of connectors are coupled to each other, the first and third pads are opposed in a direction in which a universal cord extends, and approach each other. Further, when the connectors are coupled to each other, the second and fourth pads are opposed in a direction in which the universal cord extends, and approach each other.
Information about an image inside the living body is transferred from the intracorporeal device to the extracorporeal device by capacitive coupling between the first and third pads. A control signal is transferred from the extracorporeal device to the intracorporeal device by capacitive coupling between the second and fourth pads.
In the electronic endoscope system, the first and third pads are covered with an insulator. As such, even when the endoscope is cleaned using an antiseptic solution, these pads are prevented from being corroded. Accordingly, the endoscope is not only easily cleaned but is also prevented from being corroded.